해군 함정 탑재용 전자장비 랙의 수직 기둥 단면 형상 설계에 관한 연구

Abstract

Elastic mounts are applied to electronic equipment racks (EERs) mounted on naval vessels to reduce forces transmitted from external impacts or vibration. EERs should be designed to have sufficient structural capability to address the exposed forces during its service life-cycle, and the main focus should be on the body frame because most of the stiffness of the EER is supported by the responsible body frame. An EER’s body frame can be divided into two parts, a horizontal rack and a vertical column, and the structural rigidity from the vertical columns plays an essential role in supporting the overall stiffness of the EER. This study aims to find the acceptable minimum second moment of inertia of the cross-section at a vertical column among four candidates to satisfy the required structural stiffness of the EER. The maximum stress of each cross-sectional frame structure is calculated by the transient response analysis of the body frame under the impact force according to the BV-043 specification. The feasibility of the structural stiffness is initially evaluated by the modal analysis of the finite-element model of the body frame of the EER, and it is verified by performing an experimental modal test of a prototype of the responsible body frame. The test results revealed that the designed cross-section of the vertical column is capable of supporting the EER system over the require vibration test, MIL-167-1A, because all resonance frequencies were marginally higher than the service frequency, which ranged from 4 Hz to 33 Hz.